Related Experiment Video
Updated: Jun 27, 2025
10:40
High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
7.5K
Continuous-wave GaAs/AlGaAs quantum cascade laser at 5.7 THz
Mohammad Shahili1, Sadhvikas J Addamane2, Anthony D Kim1
1Department of Electrical and Computer Engineering, University of California, Los Angeles, CA 90095, USA.
Nanophotonics (Berlin, Germany)
|April 29, 2024
Summary
Researchers explored design strategies for terahertz (THz) quantum cascade lasers (QCLs) to enhance performance near the Reststrahlen band. They achieved continuous-wave operation up to 5.71 THz, a new record for THz QCLs.
Area of Science:
- Quantum Cascade Lasers
- Terahertz Spectroscopy
- Semiconductor Devices
Background:
- Terahertz (THz) quantum cascade lasers (QCLs) face performance degradation near the Reststrahlen band.
- Improving THz QCL performance is crucial for applications in spectroscopy and imaging.
Purpose of the Study:
- Investigate design strategies to enhance THz QCL performance in the 5-6 THz range.
- Overcome performance limitations near the Reststrahlen band.
- Optimize designs for lower power dissipation and improved temperature performance.
Main Methods:
- Numerical and experimental investigations of QCL designs.
- Focus on two specific designs targeting 5.4 THz.
- Analysis of broadband gain and lasing modes.
- Evaluation of pulsed and continuous-wave (cw) operation.
Main Results:
- Broadband gain observed, with strongest modes lasing between 5.3-5.6 THz.
- Observed lasing modes ranging from 4.76 to 6.03 THz.
- Achieved pulsed operation up to 117 K and cw operation up to 68 K.
- Demonstrated a record cw operation frequency of 5.71 THz for a THz QCL.
Conclusions:
- Waveguide loss in doped contact layers and metallization critically limits performance above 5 THz.
- The developed designs show promise for high-frequency THz QCL applications.
- Further research should focus on mitigating waveguide losses for enhanced performance.
